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A new study shows that younger people born during the winter months were more likely to be thrill seekers than those born during summer months. But the reverse pattern may hold true for older adults.

The results of the study were presented last week at the annual conference of the British Psychological Society.

Birth season may affect behavior
In the study, researchers had 448 students ranging in age from 20 to 69 complete a standardized sensation-seeking scale along with background information on month of birth and age.

Researchers found that among students under 45 years, those born from October to March were more likely to be attracted to sensation-seeking behavior than those born from April to September.

But among older students, the opposite effect was found, with those born during the summer months reporting a higher level of thrill-seeking behavior than those born during the winter.

Researchers say the season in which people are born may affect behavior due to the effects of sunlight exposure on the chemicals in the brain. Age differences in these effects may be caused by age-related changes in the brain chemical balance.